Vray light testing: emisive materials

[Free Agent_cg]

ive got another question (a couple actually):

with vrays default settings on opening the primary render engine is QMC and renders this emisive witha good (although still abit too grainy) light reading... light test 01

i changed the primary render engine to Irradience map (i prefer the image quality) but just cant get away from the splotchy light... light test 02

is this a photon issue or a subdivs issue and what can i do to fix this?

there is no such thing as a stupid question... unless they're stupid.

[dalomar_cg]

Re: Vray light testing: emisive materials

Well there are a two things that could be at the root of the issue, so I'll go over both of them. The major one is that the defaults are setup with an adaptive amount of 1, which works fine for qmc, but IR hates that high of an adaptive amount. The maximum Adaptive amount that I ever really use is .95 because I use IR alot and recently I've been leaning back towards the old default setting of .85. Ultimately I think thats probably what the major cause of those artifacts are.

The second thing, and this is more of a general rule of thumb about emissive geometry, is that the number of samples that are taken depends on the mesh/faces of that object. In other words a plane with a single face will yield a noisier result then the same size plane that is broken up into several faces. So as a general rule of thumb, if your using light emitting geometry try and have it be many faces instead of just one.